oltos, you speak of directivity and diffraction. Is there a reason you are focused on horns rather than waveguides?
My other big concern are driver choices. Assuming that pursuit of a two-way system is usually preferable, has anyone experience with this? https://usspeaker.com/radian 745neoBepb-1.htm
OR: SB Audience 65 CDNT gets lots of praise for use in a two way system.
And Troy offers this.
https://josephcrowe.com/products/3d...-audience-65cdn-t?_pos=1&_psq=sb&_ss=e&_v=1.0
OR: SB Audience 65 CDNT gets lots of praise for use in a two way system.
And Troy offers this.
https://josephcrowe.com/products/3d...-audience-65cdn-t?_pos=1&_psq=sb&_ss=e&_v=1.0
A diffraction slot is not the same as fins. Diffraction slot in simple terms a "tunnel" in the throat section that effects the directivity of the horn or function as a waveguide. JBL used in for example the older 4430 and 4435 horns
The older JBL diffraction slot horns has their issues. But with modern methods, we can largerly avoid it and still have the benefit of a constant and narrow vertical directivity lower in frequency. IMO, avoiding detrimental vertical reflections is very important to sound quality.
Horns are skinny in the middle, which sacrifices the extent of the directivity attainable for a given length and mouth size. In a radial horn this is all pushed into the vertical, which is what you've been concerned about.
Given your concern, can you give a reason for choosing a horn over a waveguide?
As I said, I don't really know the difference. Show me when and where have I actually voiced a preference for a horn instead? What I do know is that it's not uncommon for even experts to use those interchangeably, such as here. https://audiohorn.net/x-shape-horn/
But if you know of one or more commercially available CD waveguides with great x and y plots and other impressive measurements please post the links for them.
Here's what's obviously a very simple primer on "waveguides", but was extremely useful for helping me to refine my goals. https://thenextweb.com/news/what-the-heck-is-a-waveguide
My only concern it where he says: "That said, waveguides often narrow directivity in the frequency range largely responsible for the perception of soundstage width. This usually means a more ‘pinpoint’ soundstage, but may come at the expense of a sense of width, or expansiveness.
Narrower directivity isn’t inherently bad or good, and research into the topic suggests it’s largely a matter of personal preference and how the speaker interacts with a particular room. Despite all the praise I’ve showered on the use of waveguides, I’m often willing to sacrifice some precision for a larger soundstage. Your mileage may vary, and this will depend on the specific recording you’re listening to as well.
And of course, the waveguide’s implementation matters. Some waveguides are meant to provide a massive amount of directivity control, while others are only meant to help refine the response a little."
Obviously, this calls for a waveguide (a name which more aptly describes the function of that device than horn) capable of an equal or otherwise satisfactory compromise between delivering a subjectively wide sound stage for a spacious and expansive sound while sacrificing next to no imaging and tonality.
My only concern it where he says: "That said, waveguides often narrow directivity in the frequency range largely responsible for the perception of soundstage width. This usually means a more ‘pinpoint’ soundstage, but may come at the expense of a sense of width, or expansiveness.
Narrower directivity isn’t inherently bad or good, and research into the topic suggests it’s largely a matter of personal preference and how the speaker interacts with a particular room. Despite all the praise I’ve showered on the use of waveguides, I’m often willing to sacrifice some precision for a larger soundstage. Your mileage may vary, and this will depend on the specific recording you’re listening to as well.
And of course, the waveguide’s implementation matters. Some waveguides are meant to provide a massive amount of directivity control, while others are only meant to help refine the response a little."
Obviously, this calls for a waveguide (a name which more aptly describes the function of that device than horn) capable of an equal or otherwise satisfactory compromise between delivering a subjectively wide sound stage for a spacious and expansive sound while sacrificing next to no imaging and tonality.
So, it would seem that, in pursuit of a two-way system, the primary goal is find a waveguide (or horn) which achieves an equal balance of these two performance parameters:
Isn’t this, for the most part, a narrowing directivity horn for minimizing early reflections?
https://cdn.shopify.com/s/files/1/0..._Filled_Contour_Plot_480x480.png?v=1697218866
https://josephcrowe.com/products/3d-cad-files-horn-no-1994-es450-biradial-for-jbl-2446-2-throat
And would this bigger and narrowing horn do so even better??
https://cdn.shopify.com/s/files/1/0...BMS_4591-8_off-axis3_480x480.png?v=1649504045
https://josephcrowe.com/products/3d-cad-plans-for-es-290-biradial-horn-horn-no-1670
Or if it did work better than the ES450, might its bigger size cause too many late reflections that would have to be reduced by room treatment?
But to attain that other half of the compromise-maximizing spaciousness, soundstage width and the sense of expansiveness-how well is that also achieved by the above horns, at least below ~ 2kHz?
Therefore, on a scale of 1 to 10, with 10 being best, how well do those Troy Crowe horns satisfy the sweet spot of that compromise?
3/) OTOH, how to rate the suitability of these horns (or waveguides as designer and forum member NicoB sometimes calls them), which are clearly constant directivity horns (if not so much vertically)?
https://audiohorn.net/x-shape-horn/
https://audiohorn.net/next-gen-bi-radial-horn/
Presumably, in terms of our compromise, would CD horns not be the best choice?
In any case, between those two CD horns which would more closely satisfy our compromise, and why?
4/) However, am I wrong or would the ES290 be the best compromise, at least for a two-way system? If not, please explain.
5/) Please suggest any commercially available horn (waveguide) which would work better.
Isn’t this, for the most part, a narrowing directivity horn for minimizing early reflections?
https://cdn.shopify.com/s/files/1/0..._Filled_Contour_Plot_480x480.png?v=1697218866
https://josephcrowe.com/products/3d-cad-files-horn-no-1994-es450-biradial-for-jbl-2446-2-throat
And would this bigger and narrowing horn do so even better??
https://cdn.shopify.com/s/files/1/0...BMS_4591-8_off-axis3_480x480.png?v=1649504045
https://josephcrowe.com/products/3d-cad-plans-for-es-290-biradial-horn-horn-no-1670
Or if it did work better than the ES450, might its bigger size cause too many late reflections that would have to be reduced by room treatment?
But to attain that other half of the compromise-maximizing spaciousness, soundstage width and the sense of expansiveness-how well is that also achieved by the above horns, at least below ~ 2kHz?
Therefore, on a scale of 1 to 10, with 10 being best, how well do those Troy Crowe horns satisfy the sweet spot of that compromise?
3/) OTOH, how to rate the suitability of these horns (or waveguides as designer and forum member NicoB sometimes calls them), which are clearly constant directivity horns (if not so much vertically)?
https://audiohorn.net/x-shape-horn/
https://audiohorn.net/next-gen-bi-radial-horn/
Presumably, in terms of our compromise, would CD horns not be the best choice?
In any case, between those two CD horns which would more closely satisfy our compromise, and why?
4/) However, am I wrong or would the ES290 be the best compromise, at least for a two-way system? If not, please explain.
5/) Please suggest any commercially available horn (waveguide) which would work better.
What I think is strange are the words to describe what is happening.... When we look what the word means, and what is happening.... is this lining up with reality? What I mean is.... when in a large space... what happens there? I thought that there was a large decline in early reflections? Familiar with what may happen with High DI..... So strange that in a spacious place, nothing happens resemblant to what is happening when in a small room and low DI... how is this acceptable? We say that early reflections cause a sense of spaciousness... but when in a literal spacious place, the opposite happens. An increase in early reflections result in the case of a lack of space.... so why can't we say that early reflections add a sense of confinement. Much more literal I think. With current definitions, Large spaces sound confined and small spaces sound Spacious? Spacious sounds confined and Confided sounds Spacious? really? Maybe I am not looking at the right point. Maybe the words are being used to describe the sound and not the space? As in, the sound is coming from all over versus confined to its true and intended position. That actually makes more sense. In that case, might it be proper to add a little more indication or specificity to the terminology?
A Low DI in a non spacious room makes the room sound for confined but the overall sound is more spacious...
A High DI in a confined room makes the room sound more spacious but the overall sound is more confined....
Overall sound might be replaced with "image"
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In my discussions, the term spaciousness is purely a psychoacoustic perception. It has nothing to do with a space being spacious in the sense of its volume.
Early reflections do add spaciousness, but nothing compared to large late arriving reflections. A large space can have these later reflections at a high level as can a small space, but the small space cannot have low early reflections while the larger one can. The situation is a continuum not a hard and fast rule of times, etc. The higher the DI the lower the early reflections and, relatively, the higher the later ones.
Early reflections do add spaciousness, but nothing compared to large late arriving reflections. A large space can have these later reflections at a high level as can a small space, but the small space cannot have low early reflections while the larger one can. The situation is a continuum not a hard and fast rule of times, etc. The higher the DI the lower the early reflections and, relatively, the higher the later ones.
My unscientific yet real experience with beamy (rising DI) horns that cover a large frequency range is that the low DI in the lower midband gives you an enveloping and large soundstage perception due to the big horn mouth, and the higher DI from the treble provides for more "pinpoint precision" at the expense of a smaller sweetspot. The "spaciousness" can be created by applying diffusers and absorption at the "right places" at the ceiling, side and back walls, to get those uncorrelated late reflections preferably coming from the undamped front of the room. In other words, to a certain degree you can "sculpt" the spaciousness with room treatments. Just focussing on the DI discussion without paying attention to the acoustics may result in less than optimal results. Of course, my findings are subjective and I cannot prove it with "science" so my experience is just one data point. But it may be worth it to experiment.
A rising DI is not constant directivity.
While we may be able to accommodate a certain small range of DI, the room geometry doesn't change for different frequencies.
This is not what one wants as spaciousness requires reflections from the side/rear and any from the front are a distraction to imaging.
This of course is true, but hard to discuss as every situation is different. I will say that correct DI, source placement and pointing, along with the rooms acoustics are all critical aspects. In my room, I have high CD DI in a room with little rear absorption and lots of absorption behind the toed-in speakers. My imaging is superb and that's what I was going for. Spaciousness in a small room is difficult to impossible to obtain because small rooms damp so quickly. This is why engineers rely so heavily on recording room ambience in the mix. But this is not really spaciousness since it comes from the speakers in front.
Yes, of course you also need reflections from the side and rear walls, but such that they are not direct/first order reflections. In my specific case I used QED diffusers on the back wall that sent uncorrelated reflections back to the front end (including front side walls). But late reflections from the front wall also contributed to the spaciousness -in my experience- so I dare to differ. The word here is "late". There was no way to damp the front wall anyway, because it was a large window pane. I did damp the front side walls around the speakers, though. And I agree that every situation is different, and experimenting with acoustics is fun and may yield even better results from one's system. Many consider the room as part of the system and I eventally found out that it was true, when I started to experiment out of frustration about persistent problems I could not solve with tweaking toe-in and placement. Things like comb filtering at the listening spot: gone with room treatment. Also, I met too many audioholics who were buying expensive cabling or $1000 interlinks and superduper snakeoil products, but never thought of improving the acoustics for a fraction of the price of a fancy cable, and as a result where never satisfied and therefore needing another superduper interlink....etc.
Correct. Not everyone wants CD though. I want a smooth, constantly rising DI. But it's a preference that goes against what many people think they prefer. Fine with me, of course. I know I will not make many friends that way -but that is o.k. 😊
I accept your choice. I think power/balance wise there is something in that.
However I also find that as you "uncover" the reflection points, they tend to be discrete as opposed to diffuse. In fact the more you get into the design, the more you realise how limited the choices are if you want to meet certain goals.. not just choice wise, but physical limitations.
However I also find that as you "uncover" the reflection points, they tend to be discrete as opposed to diffuse. In fact the more you get into the design, the more you realise how limited the choices are if you want to meet certain goals.. not just choice wise, but physical limitations.
I built my room from scratch in my basement so I was able to design the acoustics in from the get go.
They do what they can and even though it makes no difference, they convince themselves that it does. Very human.
I see that you have the Radian 745 from what you said here about the assembly issues that caused an unnecessary response peak. Luckily, you were able to banish that peak by somehow reseating (?) the diaphragm. Also, what is the felt inside used for and why was it missing? It’s pretty careless of Radian’s designers. https://www.diyaudio.com/community/threads/18-sound-nd3st-compression-driver.300974/page-3 post 41. But I'm very sure that Pierre caught those oversights with his build.
NicoB describes his horns as constant directivity but based on the Geddes plots shown here how true is this? https://audiohorn.net/x-shape-horn/
https://audiohorn.net/next-gen-bi-radial-horn/
What problems, if any, do you still have with those two horns?
Might this or another be a good CD horn choice for the Radian 745Be?
http://oem.ciare.com/en/299/450/prodotti.php
Just a side note. It's possible to achieve spaciousness from the front wall as well. With dipoles, sufficient distance from speakers to the front wall and ideally diffusers placed there.
It would be good to clarify this. It almost seems it's an all or nothing deal. Anything in between might be more of a problem than the sliding scale of spaciousness I've read about.